3 unidentifiable green orbs were seen flying in the sky on a cloudy night.

I looked out of my window because I noticed a light green light moving very rapidly. I could not tell exactly what shape it was, because the sky was covered in clouds, but it was a definite green orb moving sporadically around the sky. I then noticed two more green lights moving with it, also sporadically. They moved very fast and turned sharply and quickly. There was no real pattern to their movements at first, but then they formed a large circle in the sky and seemed to move on a fixed rotation around the circle. At the exact same time they would change directions. They would alternate between this pattern of sporadic movement with each other and the circle. This lasted for about 30 minutes before one seemed to disappear suddenly, then another one a few minutes later, and the last one about 10 minutes after that. The only other person who I know saw this is my sister, who I woke up after watching the green lights in the sky for 10 minutes. I have never seen anything like this before in my life (the only time I've ever seen anything like it was on a show discussing UFOs, and there were videos that people submitted that resembled what I saw).